Timer control for textile folding machines or the like



June 10, 1969 R. L..SJOSTR OIM TIMER CONTROL FOR TEXTILE FOLDING MACHINES OR THE LIKE Sheet Filed Feb. 27. 1968 g w/ro/e WW M June 10, 1969 R. L. SJOSTROM TIMER CONTROL FOR TEXTILE FOLDING MACHINES QR THE LIKE Filed Feb. 27, 1968 heet United States Patent US. Cl. 307141 6 Claims ABSTRACT OF THE DISCLOSURE A timer for use with a textile folding machine or similar or similarly functioning machine. The timer consists essentially of two aligned motors operating at different but related speeds. These motors are connected to electrical contacts which are moved over the same path in opposite directions. A microswitch is engaged by an article as it passes over a conveyor for a time period which is equivalent to a measured length of the article. This switch is electrically connected to one motor which causes the contact on this one motor to move at a given speed over a selected distance from the initial starting position. When the article is disengaged from the switch, the motor stops rotating and the contact stops at a second position. At a subsequent time the article moves into engagement with a second switch which cause the second motor to rotate at a second faster speed as for example, a speed twice the speed of the first. Thus, the electrical contact connected to the second motor reaches the second position at which the first switch is located in half the time it took the first switch. When the second electrical contact reaches the second electrical contact a circuit is closed from a power supply to a time delay relay. This time delay relay in turn causes a solenoid to operate for a time period, depending upon the selected parameters of the time delay relay. This solenoid may be used to control an air valve and thereby efiect a fold or other function on the article being carried at a line halfway along the length of the article.

Background of the invention There is an ever present requirement for improved time mechanisms designed for use with textile handling equipment, and in particular, with folding means designed to handle pillow cases, towels, sheets and other linen and laundry supplies. Heretofore, sheet and small piece foldin-g equipment have used a variety of timing mechanisms for effecting a sequence of folds in the linen and laundry supplies being handled in the machinery These timing mechanisms however have not been altogether satisfactory in operation because of difiiculties in designing equipment for use with textiles having varying weights and densities and with textiles which can vary in texture and weight from time to time depending on their water content. The timers which have been designed heretofore are ordinarily uncertain of consistent operation, cannot be adjusted easily for varying materials and in many instances are comparatively complicated and expensive.

Brief description of invention 3,449,592 Patented June 10, 1969 inexpensive modular timer mechanism which may be utilized in any fabric handling equipment requiring an actuating signal at a selected time after two successive input signals. One of the objects of the present invention is to provide a mechanism whereby successive input signals of related time durations are used to generate an output signal at an instant which is related to the time duration of the input signals with which it is associated. Another object of the present invention is to provide an improved mechanism for a sheet folder or small piece folder.

In the present invention there is provided a pair of switches with each connected to a separate motor for actuating the motor. Each of these motors has an output means which moves an electrical contact at different relative speeds. These contacts are arranged to be moved over the same preferably continuous paths so that upon sucessive actuation of the motors with the electrical contacts starting at the same initial positon, both contacts will reach the same second position, but at different relative rates of speed. These contacts are connected through time delay relay mechanism for actuation of an output signal by a mechanism for a prescribed period of time after termination of the second input signal with the time interval between the start of the second input signal and the output signals a function of the time duration of the first input signal.

Brief description of the drawings These objects and advantages of the present invention will be more clearly understood when considered in conjunction with the accompanying drawings in which:

FIG. 1 is a schematic view of an electrical circuit embodying the present invention;

FIG, 2 is a fragmentary plan view of a timer embodying the circuit of FIG. 1; and

FIG. 3 is a view taken substantially from the left of FIG. 2.

Detailed description of preferred embodiments The circuit shown in FIG. 1 ma be used in a variety of machines where two successive inputs of equal duration are used to actuate an output at a predetermined time interval following the start of second input. In particular the circuit is adapted for use with folding equipment for textile articles such as towels, sheets and blankets. In such machines the circuit is used to actuate folding mechanisms. For example, a towel moving through a folding machine engages switches which successively actuate the circuit and thus cause the circuit to actuate a folding mechanism at the center of the towel after the leading edge of the towel preaches a particular point in the folding machine.

Referring specifically to FIG. 1 there is a measuring switch 1 supported on the machine and adapted to be engaged by textile articles as they move through the machine. A microswitch having an actuating arm projecting between adjacent conveyor belts into the path of the article is suitable. This switch arm is depressed and the switch 1 thereby closed for a time period over which the article passes the switch arm. Closing switch 1 causes the clutch windings 2 of the synchronous motor 3 to be energized. Energy is supplied from the power source 4 which may be volts at 60 cycles through the positive lead 5 with a return path through ground lead 6. Switch 7 is a master power switch and 8 is fuse. The armature windings 10 of motor 3 and armature windings 11 of motor 12 are normall energized through positive leads 5 and return leads 6 to ground. Thus when clutch windings 2 are energized, a clutch integral with the motor constructions interengages the output shaft 14 with the already rotating armature. The output shaft 14 (FIGS. 2 and 3) carries a contact arm which rotates in a counter clockwise direction over an arc having a length dependent upon the length switch 1 is depressed and upon the rotational speed of the motor 3. We may assume that motor 3 is a 30 r.p.m. motor and switch is depressed one second. Under these conditions arm 15 will describe an arc of 180. In any event it is important that parameters of the device are selected such that the textile articles normally handled by the device will cause arm 15 to move over sufficiently far to be contacted by arm 26 hereafter described when it is moved. This distance may be determined by dividing 360 by one plus the fractional ratio of the speed of arm 26 to arm 15. The towel continues to move through the machine and subsequently engages the fold switch for a time period preferably of the same length as switch 1 was engaged. This causes clutch windings 21 of motor 12 to energize thus actuating the integral clutch (not shown) of motor 12 causing its shaft 23 to interengage its already rotating armature. The windings 21 are energized through positive leads 22 in series with relay 24 and ground lead 25. Shaft 23 preferably rotates in a clockwise direction and in the specific example motor 12 is a 60 r.p.m. motor. Thus the shaft 23 carries contact arm 26 in a clockwise direction at twice the speed of arm 15. Since switch 20 is closed for the same length of time as switch 1 by the same textile article that just closed switch 1, arm 26 moves over an equal length of an arc in half the time as arm 15. Under these conditions the contact arm 26 will come into electrical contact with arm 15 when it has moved over an arc of 180. As previously noted the parameters of both the device and the articles passing through it must be such as to assure the contact of arms 15 and 26. In the present case therefore the article passing through must cause arm 15 to move over an arc of at least 120. This is determined by dividing 360 by one plus the ratio of the speed of arm 26 to arm 15 or:

(D-PG) When arms 15 and 26 are in electrical contact with one another coil 30 of relay 24 is energized through positive lead 31, rectifier 32, limiting resistor 33 and ground lead 6A. Contacts 35 and 36 of relay close to terminals 35A and 36A respectively on energization of coil 30. Movement of contact 35 from terminal 35B to 35A breaks the circuit through clutch coil 21 and thereby stops movement of arm 26 very quickly. The movement of contact 36 to terminal 36A energizes coil 40 of time delay relay 41. This causes arms 42 and 43 to move respectively to terminals 42A and 43A. When arm 42 closes to terminal 42A power is supplied from positive lead 45 through arm 42, terminal 42A to lead connected to time delay relay 51. Power is thereby supplied through arms 52 and 53 which are closed respectively to terminals 52A and 53A of the time delay relay 51 to coil 54 via lead 55. Coil 54 is part of a solenoid (not shown) which in turn forms a part of the folding means. Thus coil 55 may actuate a solenoid arm in turn controlling a valve in an air line. When the coil 55 is energized the valve opens admitting air from an air reservoir through a conventional air blast pipe or folding mechanism. As indicated both relays 41 and 51 are time delay relays. Preferably they are adjustable over a period of .1 second to 5 seconds. Such relays are G. C. Wilson model 591-16 relays. Relay 41 is adjustable through the adjustable time delay coil 40 for pu oses of varying the specific time that coil 54 is actuated relative to the electrical engagement of arms 15 and 26. Thus variations of the line at which the textile article is folded may be effected. The time duration of the air blast is controlled by relay 51 through adjustment of variable resistor 58. Depending on the adjustment arms 52 and 53 will remain closed to terminals 52A and 53A for a time duration of .1 second to 5 seconds and will thereafter permit arms 52 and 53 to open automatically.

What is claimed is:

1. A timer comprising:

a pair of motor means operable at different but related speeds,

a pair of contact means carried one by each of said motor means and adapted to be moved over paths from common first positions to common second positions with the contact means in electrical engagement when both are in the same common position,

a pair of switch means adapted to be sequentially actuated for the same time periods,

circuit means electrically connecting one of said switch means to one motor means whereby actuation of said one switch means causes said one motor means to move the contact means carried by it from said one position to said second position in a first time interval related to the time period that said one switch means was actuated, said circuit means also electrically connecting said otherswitch means to said other motor means whereby actuation of said other switch means for the same time period causes said other motor means to move the contact means carried by it from said one positon to said second position in a second time interval related to said first time interval in proportion to the related speeds of said motor means,

and said circuit means including portions for actuating an output signal means when said contact means are both moved to said second positions.

2. A device as set forth in claim 1 wherein said output signal means comprises a solenoid adapted to actuate a valve.

3. A device as set forth in claim 2 wherein said circuit means includes a first time delay relay for varying the time duration of said output signal.

4. A device as set forth in claim 3 wherein said circuit means includes a second time delay relay for varying the point in time at which said output signal is initiated relative to actuation of said other switch means.

5. A device as set forth in claim 4 wherein said electrical circuit includes a relay for controlling power to at lease one of said time delay relays.

6. A timer as set forth in claim 1 wherein said motor means comprise a pair of motors positioned in opposed alignment with aligned shafts having radially projecting arms each carrying one of said contact means for movement in opposite directions.

References Cited UNITED STATES PATENTS 2,011,934 8/1935 Kahn 270-68 2,940,751 6/1960 Buss 270-81 X 3,212,771 10/1965 Kerman et al 27081 X ROBERT K. SCHAEFER, Primary Examiner.

T. B. IOIKE, Assistant Examiner.

US. Cl. X.R. 270-81; 317-441 

